1. Field of the Invention
The present invention relates to a turning control system for use in a track-laying vehicle and, more particularly, to a turning control technique for turning track-laying vehicles such as a bulldozer, power shovel or crane rightwards or leftwards by driving, with a steering motor, crawler belts provided at both sides of the vehicle such that a relative travel difference is caused between the crawler belts.
2. Description of the Prior Art
In a conventional track-laying vehicle, turning control is performed such that, if a steering lever, for example, is operated and placed in a certain displacement position, the revolution speed of the steering motor will be maintained constant, that is, the relative travel difference between the crawler belts provided at both sides of the vehicle will be maintained constant, irrespective of the vehicle speed at which the vehicle moves forwards or backwards. Such a steering lever is one form of a steering instructing means which can be displaced from a neutral position by operation and which instructs, according to the direction and distance of its displacement, a turning direction and a turning radius for the vehicle, the turning radius decreasing as the displacement distance increases.